In the case of conventional video conferencing, functional supports such as H.239, BFCP (Binary Floor Control Protocol), and the like are required so as to share a content between remote places, such that the conventional video conferencing has a major drawback in that a conferencing participant using a terminal which does not support a content-sharing function can not participate therein. More specifically, it is because that the aforementioned method is based upon a dual-channel type where one channel configured for conveying a user image and a user voice and the other channel configured for conveying data to be shared are separated each other and are operated respectively.
Furthermore, in the case of some of the old fashioned codec equipment, PC images or other image sources are received through an external source connecting device, based on which a user image is synthesized and transmitted in PIP (Picture in Picture) mode. However, the method just described above results in an economic burden in that codec hardware equipment should be additionally provided. Additionally, a user may feel that the PIP image is old fashioned, that is to say the user may feel that the PIP image falls behind in technology, and further a simple image is applied as a background image, thereby causing a limit where users can not interact with each other, etc.
Additionally, in such a video call method using a 3D depth camera at an initial stage, a video conferencing terminal mounted with the 3D depth camera is configured to fill a background of an extracted image according to resolution (CIF, VGA, and the like) supported by the 3D depth camera, such that resolution of a background content becomes deteriorate due to the resolution limitations thereof, etc. As a result, the video call method mentioned hereinabove may have a limitation of being used, for example, for privacy protection purpose where a user may hide a user's surrounding, rather than sharing a background content with other users, and further may have problems that a sound of the background content can not be applied to the video call method and the background content can not be interacted with by other users.